<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>apple button</title>
</head>
<body>
<div id="div1">
<div id="div2"></div>
</div>
</body>
</html>
<style>
#div1{
width: 170px;
height: 100px;
border-radius: 50px;
position: relative;
border:3px solid rgba(0,0,0,0.15);
}
#div2{
width: 96px;
height: 96px;
border-radius: 48px;
position: absolute;
background: white;
box-shadow: 0px 2px 4px rgba(0,0,0,0.4);
}
.open1{
background: rgba(0,184,0,0.8);
}
.open2{
top: 2px;
right: 1px;
}
.close1{
background: rgba(255,255,255,0.4);

border-left: transparent;
}
.close2{
left: 0px;
top: 0px;
border:2px solid rgba(0,0,0,0.1);
}	
</style>

<script>
window.onload=function(){
var div2=document.getElementById("div2");
var div1=document.getElementById("div1");
div2.onclick=function(){
div1.className=(div1.className=="close1")?"open1":"close1";
div2.className=(div2.className=="close2")?"open2":"close2";
}
}	
</script>
